cvelist/2025/21xxx/CVE-2025-21702.json
2025-03-13 13:00:32 +00:00

168 lines
10 KiB
JSON

{
"data_version": "4.0",
"data_type": "CVE",
"data_format": "MITRE",
"CVE_data_meta": {
"ID": "CVE-2025-21702",
"ASSIGNER": "cve@kernel.org",
"STATE": "PUBLIC"
},
"description": {
"description_data": [
{
"lang": "eng",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\npfifo_tail_enqueue: Drop new packet when sch->limit == 0\n\nExpected behaviour:\nIn case we reach scheduler's limit, pfifo_tail_enqueue() will drop a\npacket in scheduler's queue and decrease scheduler's qlen by one.\nThen, pfifo_tail_enqueue() enqueue new packet and increase\nscheduler's qlen by one. Finally, pfifo_tail_enqueue() return\n`NET_XMIT_CN` status code.\n\nWeird behaviour:\nIn case we set `sch->limit == 0` and trigger pfifo_tail_enqueue() on a\nscheduler that has no packet, the 'drop a packet' step will do nothing.\nThis means the scheduler's qlen still has value equal 0.\nThen, we continue to enqueue new packet and increase scheduler's qlen by\none. In summary, we can leverage pfifo_tail_enqueue() to increase qlen by\none and return `NET_XMIT_CN` status code.\n\nThe problem is:\nLet's say we have two qdiscs: Qdisc_A and Qdisc_B.\n - Qdisc_A's type must have '->graft()' function to create parent/child relationship.\n Let's say Qdisc_A's type is `hfsc`. Enqueue packet to this qdisc will trigger `hfsc_enqueue`.\n - Qdisc_B's type is pfifo_head_drop. Enqueue packet to this qdisc will trigger `pfifo_tail_enqueue`.\n - Qdisc_B is configured to have `sch->limit == 0`.\n - Qdisc_A is configured to route the enqueued's packet to Qdisc_B.\n\nEnqueue packet through Qdisc_A will lead to:\n - hfsc_enqueue(Qdisc_A) -> pfifo_tail_enqueue(Qdisc_B)\n - Qdisc_B->q.qlen += 1\n - pfifo_tail_enqueue() return `NET_XMIT_CN`\n - hfsc_enqueue() check for `NET_XMIT_SUCCESS` and see `NET_XMIT_CN` => hfsc_enqueue() don't increase qlen of Qdisc_A.\n\nThe whole process lead to a situation where Qdisc_A->q.qlen == 0 and Qdisc_B->q.qlen == 1.\nReplace 'hfsc' with other type (for example: 'drr') still lead to the same problem.\nThis violate the design where parent's qlen should equal to the sum of its childrens'qlen.\n\nBug impact: This issue can be used for user->kernel privilege escalation when it is reachable."
}
]
},
"problemtype": {
"problemtype_data": [
{
"description": [
{
"lang": "eng",
"value": "n/a"
}
]
}
]
},
"affects": {
"vendor": {
"vendor_data": [
{
"vendor_name": "Linux",
"product": {
"product_data": [
{
"product_name": "Linux",
"version": {
"version_data": [
{
"version_affected": "<",
"version_name": "57dbb2d83d100ea601c54fe129bfde0678db5dee",
"version_value": "78285b53266d6d51fa4ff504a23df03852eba84e"
},
{
"version_value": "not down converted",
"x_cve_json_5_version_data": {
"versions": [
{
"version": "2.6.34",
"status": "affected"
},
{
"version": "0",
"lessThan": "2.6.34",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.4.291",
"lessThanOrEqual": "5.4.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.10.235",
"lessThanOrEqual": "5.10.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.15.179",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
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},
{
"version": "6.1.130",
"lessThanOrEqual": "6.1.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.6.83",
"lessThanOrEqual": "6.6.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.12.14",
"lessThanOrEqual": "6.12.*",
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{
"version": "6.13.3",
"lessThanOrEqual": "6.13.*",
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},
{
"version": "6.14-rc2",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
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"defaultStatus": "affected"
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"references": {
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{
"url": "https://git.kernel.org/stable/c/78285b53266d6d51fa4ff504a23df03852eba84e",
"refsource": "MISC",
"name": "https://git.kernel.org/stable/c/78285b53266d6d51fa4ff504a23df03852eba84e"
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{
"url": "https://git.kernel.org/stable/c/7a9723ec27aff5674f1fd4934608937f1d650980",
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"name": "https://git.kernel.org/stable/c/7a9723ec27aff5674f1fd4934608937f1d650980"
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{
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"name": "https://git.kernel.org/stable/c/a56a6e8589a9b98d8171611fbcc1e45a15fd2455"
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"url": "https://git.kernel.org/stable/c/020ecb76812a0526f4130ab5aeb6dc7c773e7ab9",
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"name": "https://git.kernel.org/stable/c/020ecb76812a0526f4130ab5aeb6dc7c773e7ab9"
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"name": "https://git.kernel.org/stable/c/79a955ea4a2e5ddf4a36328959de0de496419888"
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"url": "https://git.kernel.org/stable/c/e40cb34b7f247fe2e366fd192700d1b4f38196ca",
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"name": "https://git.kernel.org/stable/c/e40cb34b7f247fe2e366fd192700d1b4f38196ca"
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"name": "https://git.kernel.org/stable/c/b6a079c3b6f95378f26e2aeda520cb3176f7067b"
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"url": "https://git.kernel.org/stable/c/647cef20e649c576dff271e018d5d15d998b629d",
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